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Rangpur Lime As a Citrus Rootstock in Florida

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78 FLORIDA STATE HORTICULTURAL SOCIETY, 1970 crements and losses through evapotranspiration including types of systems, power units and pumps. Univ. Fla. Ag. Eng. Mimeo Rept.. 65-9. can be maintained. Tailored to the individual 10. , and R. E. Choate. 1968. Selection of pumps and power units for irrigation systems in Florida. situation (soil type, drainage, rooting depth, Fla. Ag. Ext. Serv. Circ. 330. etc.), this method takes much of the "guesswork" 11. Koo, R. C. J. 1963. Effects of frequency of irriga tion on yield of orange and grapefruit. Proc. Fla. State out of the irrigation system. Hort. Soc. 76: 1-5. 12. 1969. Evapotranspiration and soil moisture determination as guides to citrus irrigation. Proc. Conclusion First Int'l. Citrus Symposium, Univ. of Calif., Riverside 3: 1725-1730. 13. Koo, R. C. J., and G. T. Hurner. 1969. Irrigation re In conclusion, the irrigation operation, inte quirements of citrus grown on Lakewood fine sand. Proc. Fla. State Hort. Soc. 82: 69-72. grated with drainage in the total water manage 14. , and A. A. McCornack. 1965. Effects ment system, is an expedient to economic produc of irrigation and fertilization on production and quality of 'Dancy' tangerine. Proc. Fla. State Hort. Soc. 78: 10-12. tion of citrus only when all aspects of the opera 15. Muma, M. H. 1970. Environment and control of in jurious insects and mites in Florida citrus groves. Cit. Ind. tion are properly planned. The risks of high Mag. 51(6): 4, 26. costs, with no value for the operation, are so 16. Phillips, R. L. 1969. Performance of closely spaced trees. Proc. Fla. State Hort. Soc. 82: 48-51. great that the use of the limited resources of 17. Reitz, H. J., and W. T. Long. 1955. Water table fluctuations and depth of rooting of citrus trees in the capital should be carefully budgeted. In the final Indian River area. Proc. Fla. State Hort. Soc. 68: 24-29. analysis, however, irrigation can be a very eco 18. Reuss, L. A. 1969. Yield response and economic feasibility of sprinkler irrigation of citrus, central Florida. nomic and desirable production practice. Univ. Fla. Econ. Mimeo Rept. EC 69-10. 19. , and D. S. Harrison. 1969. Inputs and costs of selected sprinkler irrigation systems for citrus LITERATURE CITED in central Florida. Univ. Fla. Econ. Mimeo Rept. EC 69-8. 20. Schirard, J. B. 1969. In-place rejuvenation. Cit. Ind. 1. Bryan, O. C. 1962. The response of young trees to Mag. 50(10) : 7. lime mixed with the soil profile in Leon-lmmokalee fine 21. Schmidling, J. 1970. They're taming the water sands. Cit. Ind. Mag. 43 (9): 9-10. table on flatwood soils. Fla. Gr. and Rancher (N. Ed.) 63(1): 2. Calvert, D. V., R. C. J. Koo, and H. W. Ford. 1967. 8, 25. Flood irrigation studies with citrus. Proc. Fla. State Hort. 22. Sites, J. W. 1947. Internal fruit quality as related to Soc. 80: 79-85. production practices. Proc. Fla. State Hort. Soc 60: 55-62. 3. , and H. J. Reitz. 1965. Salinity of 23. , L. C. Hammond, R. G. Leighty, W. water for sprinkle irrigation of citrus. Proc. Fla. State Hort. O. Johnson, and K. D. Butson. 1964. Information to con Soc. 78: 73-78. sider in the use of flat woods and marshes for citrus. Fla. Ag. 4. Choate, R. E., and D. S. Harrison. 1968. Irrigation Expt. Sta. Circ. S-135-A. by the accounting method. Univ. Fla. Ag. Eng. Mimeo 24. , H. J. Reitz, and E. J. Deszyck. 1951. Rept. 68-5. Some results of irrigation research with Florida citrus. 5. Driscoll, P. J. 1969. Renovating old citrus groves. Proc. Fla. State Hort. Soc. 64: 71-79. Cit. Ind. Mag. 50(3) : 22-24. 25. Tucker, D.P.H., and R. L. Phillips. 1967. Tree size 6. Ford, H. W. 1954. The influence of rootstock and control in citrus groves of the future. Cit. World 4(6) : 16-17, tree age on root distribution of citrus. Proc. Am. Soc. 26. Hort. Sci. 63: 137-142. 26. Young, T. W. 1953. Soil moisture relations in the 7. 1954. Root distribution in relation coastal citrus areas of Florida. Fla. Ag. Expt. Sta. Bui. 526 to the water table. Proc. Fla. State Hort. Soc. 67: 30-33. 27. Ziegler, L. W. 1955. Irrigation studies with Marsh 8. 1964. The effect of rootstock, soil grapefruit on Lakeland fine sand in central Florida. Proc. type, and soil pH on citrus root growth in soils subject Fla. State Hort. Soc. 68: 39-41. to flooding. Proc. Fla. State Hort. Soc. 77: 41-45. 28. 1970. The evaluation of soils for 9. Harrison, D. S. 1965. Citrus irrigation in Florida, citrus production in Florida. Cit. Ind. Mag. 51(1): 14-15. RANGPUR LIME AS A CITRUS ROOTSTOCK IN FLORIDA Mortimer Cohen because of its susceptibility to foot rot, exocortis, and xyloporosis. Observations made in experi Indian River Field Laboratory mental plantings illustrate the productivity, high Fort Pierce quality and good survival record of orange and grapefruit trees on this stock with and without Abstract exocortis. Exocortis often appears to induce a condition of dwarfing which could be desirable. 'Rangpur' lime (Citrus limonda Osbeck) is the The generally good experience of growers in 17 main rootstock used in Brazil but it has had only young commercial groves with a number of scion limited acceptance as a citrus rootstock in Florida varieties is described. The setting-out of new, selected, small plantings on 'Rangpur' lime root- Florida Agricultural Experiment Station Journal Series stock is justified. No. 3748. COHEN: RANGPUR FOR ROOTSTOCK 79 Introduction this country were propagated from budwood which carried this virus. The discovery that Constantly changing conditions in the citrus exocortis is a virus disease was made in 1949 industry keep the citrus grower on a never-end (2). Knowledge that 'Rangpur' lime is suscep ing quest for new rootstocks. The perfect root- tible to exocortis came in 1952 (14) and it was stock will, perhaps, never be found but any only in 1964 (3) that a practical and rapid means grower can cite the deficiencies of the stocks of indexing for exocortis was discovered. Even currently in most common use in Florida. The more recent are the concepts that the biggest advent of tristeza could mean calamity to groves trees are not necessarily the best and that the on sour orange (Citrus aurantium L.) stock and ability of exocortis and other viruses to induce a new problem, young tree decline, threatens new the production of small trees was a proper sub groves on rough lemon (C. jambhiri Lush.). A ject for serious study and consideration (1, 5, host of other factors make * Cleopatra' mandarin 12). Very important also is an understanding (Citrus reshni Hort. ex Tan.) and sweet orange of the existence of different strains of exocortis (Citrus sinensis (L.) Osbeck) less than perfect. virus whose effect on trees ranges from negligible Some other stocks, like trifoliate orange (Pon- to drastic (4). Under these circumstances it is drus trifoliata (L.) Rafinesque), 'Carrizo' not surprising that few studies of the interaction citrange (Poneirus X C. sinensis) and Citrus of exocortis strain, rootstock and environment macrophylla Wester are well worth trying on an are available. experimental basis in small plantings but ex In 1960 Sinclair and Brown (19) reported on perience with them is limited. This paper deals the effect of exocortis disease on 9-year old navel with another stock which is not well known to orange (Citrus sinensis (L) Osbeck) trees on the grower but about which information is now 'Cleopatra' mandarin, sweet orange, trifoliate becoming available. orange and 'Rangpur' lime. They found both 'Rangpur' lime is not unknown in the world yield and trunk circumference reduced for all scene. It is the most important rootstock of cit combinations. Olson and Shull (15) studied 12- rus in Brazil (13) and is also used in Argentina. year old 'Valencia' orange scions with and with It apparently originated in India (18) and out exocortis and xyloporosis virus on various seedling plants can be found in almost every rootstocks. Their data for trees on 'Rangpur' citrus-growing country. 'Rangpur' lime as a and other mandarin-limes showed that trees rootstock has been the subject of contradictory carrying the viruses were greatly reduced in size reports which often had their basis in the and yield as compared with uninfected trees. In changes in character of this stock when infected contrast, exocortis and xyloporosis infection pro with different strains of exocortis and xyloporo- duced relatively little depression of growth and sis. Results of some experiments are presented yield of trees on 'Cleopatra' mandarin, rough here which may help resolve some of the con lemon and sour orange. tradictions. Also given is a summary of grower In a study of the ability of citrus roots to experience with 'Rangpur' rootstock in 17 situa survive flooding, Ford (9) had one test involving tions on more than 400 acres of grove. 'Rangpur' lime. He found that 'Rangpur' and It will be seen that not only is 'Rangpur' lime 'Carrizo' were somewhat less damaged than a promising rootstock for Florida when used 'Milam' lemon and rough lemon and distinctly under virus-free conditions but controlled and better than Poneirus trifoliata, sweet orange, selected virus inoculation of this stock may give sour orange and 'Cleopatra' mandarin. the grower unprecedented flexibility in control of tree size and of the solids content of the In some reports 'Rangpur' was found to in juice. duce as much cold susceptibility as rough lemon (7, 11) while in others trees on 'Rangpur' were observed to be somewhat more resistant to cold Characteristics op 'Rangpur' Lime as a than those on rough lemon (8, 10).
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  • Citrus Rootstocks: Their Characters and Reactions

    Citrus Rootstocks: Their Characters and Reactions

    CITRUS ROOTSTOCKS: THEIR CHARACTERS AND REACTIONS (an unpublished manuscript) ca. 1986 By W. P. BITTERS (1915 – 2006) Editor, digital version: Marty Nemeth, Reference Librarian, UC Riverside Science Library, retired Subject matter experts, digital version: Dr. Tracy Kahn, Curator, UC Citrus Variety Collection Dr. Robert Krueger, Curator, USDA-ARS National Clonal Germplasm Repository for Citrus & Dates Toni Siebert, Assistant Curator, UC Citrus Variety Collection ca. 1955 ca. 1970 IN MEMORIUM Willard P. Bitters Professor of Horticulture, Emeritus Riverside 1915-2006 Born in Eau Claire, Wisconsin, in June, 1915, Dr. Willard “Bill” Bitters earned his bachelor’s degree in biology from St. Norbert College and his master’s degree and Ph.D. from the University of Wisconsin. After earning his doctorate, he first worked as the superintendent of the Valley Research Farm of the University of Arizona in Yuma, and joined the Citrus Experiment Station, in Riverside in 1946 as a Horticulturist. In 1961, Dr. Bitters became a Professor in the newly established University of California-Riverside. His initial assignment was to work on horticultural aspects of tristeza, a serious vector-transmitted virus disease which threatened to destroy California citrus orchards. Tristeza was already in California and spreading in 1946. At that time most citrus trees in California were grafted on a rootstock that was known to be susceptible to tristeza. Dr. Bill Bitters was responsible for screening of over 500 cultivars to determine which rootstock-scion combinations were resistant to this disease and yet possessed suitable horticultural characteristics. Of the 500 screened, most were susceptible, but several successful ones were selected and released to the industry.